added HMAC support to PassHash class FS#2794
use HMAC in media_token FS#2794
use hmac for external ressource hash FS#2794
use HMAC for CSRF security tokens FS#2794
use HMAC in password reset token FS#2794
make password reset token completely random

No need for HMAC here because there's no length attack vector here. We
only care for the existance of the file and each reset request is
completely (random) independent from each other.
moved X-UA-Compatible from meta tag to be sent by http header instead
Merge pull request #226 from splitbrain/hmac

Implement HMAC for signature tokens
we now require PHP 5.2.0 at least
Korean language update
treat empty AD credentials as NULL values FS#2781
fix ldap deref option FS2798

Do not pass timelimit and deref settings to ldap_search. These values
should be set globally via ldap_set_option() instead (as we do for
deref).
fix problem when ldap returns no groups FS#2788